[mrep]

The only companies the government is propping up are the airlines and small businesses by mainly paying for their payroll to keep people employed through the CARES act [0]. In what way is the government protecting large companies?

[0]: https://en.wikipedia.org/wiki/CARES_Act

[vsareto]

Exactly, it's protecting large airlines from going under. This means there's less risk here than if the government had not intervened. Any future pandemic will likely result in a similar response, therefore, airline stocks have reduced risk of becoming worthless.

At a basic level, if you removed all demand for airlines, you'd say "well, airlines don't look like a great investment". But now the demand matters less during disasters because demand isn't actually keeping the company alive as in most businesses.